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First we calculate expectation of Poisson distribution which is given as :

λ  =  n p

Here n = 20 and p = 0.1

So  λ  =  2..

Hence P(X <= 2) where X is no of pens picked = e-2 ( 20 / 0! + 21 / 1! + 22 / 2!)

                                                                    =  e-2 ( 1 + 2 + 2)

                                                                    =  5 / e2

                                                                    =  0.677

Hence P(X > 2)     =   1  -  0.677                 =    0.323 

Hence 0.323 should be correct answer..

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